1. Field of the Invention
This invention relates to a shape measuring apparatus. More particularly, it relates to a shape measuring apparatus of the type in which a predetermined pattern is projected onto an object to be measured, each point of the object to be measured being particulated, a data based on a projection pattern being detected from the object to be measured on which the pattern is projected, the detection data being processed, thereby to obtain a shape of the object to be measured by measuring the coordinate at the respective point positions on the object to be measured by means of non-contact measurement.
2. Description of the Related Art
Heretofore, there has been known a non-contact type shape measuring apparatus in which a predetermined pattern is projected to an object to be measured and this pattern is detected from two directions to decide a corresponding point between the respective detection outputs and, based on the foregoing, the shape of the object to be measured is measured.
In recent years, in such non-contact type shape measuring apparatus, since a high accuracy and high resolution measurement is required, projection pattern images are projected to an object to be measured using plural kinds of patterns and every time the respective patterns are projected, projection data is detected so as to correspond the respective data points relative to one another when the respective patterns are projected, thereby to measure the shape of the object to be measured highly accurately.
3. Problems to be Solved by the Invention
However, in order to perform a high accuracy measurement of an object to be measured in the above-mentioned non-contact type shape measuring apparatus, plural kinds of patterns are separately required. In addition, in order to project the plural kinds of patterns to the object to be measured and to correspond the data with the respective projected patterns, the relative positions of the plural kinds of patterns must be strictly decided. Thus, the apparatus is required to be made large in size and complicated adjusting means are required.